Truck.



Gf-L. MASON.

TRUCK.

APPLICATION FILED MAY 21, 1913.

atented Mar. 7, 1916.

2 SHEETS SHEET l- INVENTOR. Geargeliffaaozz.

BY y CZ I VITNESSES:

A TTORNE Y.

G. L. MASON.

TRUCK APPUCATION FILED MAYZh 1913.

1 174 5968 tentei 2, 1916,

2 SHEETS-shin 2.

. G-EOBG-EL. l llh Oll, OF W'AR-EHUUSE PQENCF,

CONNECTICUT, ASSIGNO P. CLARK COMPANY, OF EVINDSQR LUGKS, CONNECTECU'E,fa CfiR- OEAEIGIDI OIEGDN- ilettersJPatent.

NECTICUT.

Lliiilfig}? Specification of To all 'w/wm it may concern Be it knownthat l, La Mason, a citizen of the United States of rlfinlerica residingat Warehouse Point, in the county of Hartford and State of Connecticut,have invented new and useful Improvements in Trucks, of which thefollowing isa specification. l

This invention, relates to an elevating truck. As pointed out in myeo-pending application, Serial No, 768,912, filed May 21, 1913, trucksof this character heretofore constructed hare all been objectionablebecause unsound on mechanical theory. These trucks, in general, comprisea base portion and a liftingplatforni, together with a steering handleand means whereby the platform is elevated when the steering handle isdepressed; but, in so far as l have been aware and before my invention,the lifting devices for the platform have been so arranged that theyeither take their greatest in cement to correspond with the beginning ofthe down ward movement of the steering handle or the movement of theplatform 1 and handle corresponds th oughout, the upward move ment ofthe platform either falling oft or remaining the same as the handlecontinues to be depressed. My invention, on the other hand in additionto numerous other teatures some of which {shall point out particularlyhereinafter, involves arrange ment whereby. the lift of the platformtakes place very slowly the time When the handle is beginning to bedepressed the rate of up 'ard movement of the platform increasingthereafter, thus giving an {fees-y start as opposed .to the stifi startof de vices heretofore constructed for this pur pose. This is animportant advantage, for the reason that the loads tobe raised by theplatform of these trucks frequently are con siderably over a ton inWeight, and therefore mechanisms which enable the operator to get apurchase ,on the load at the he ginning of its upward movement areimportant and highly desirable Another all important advantage inherentin my new truck is involved in the arrangement whereby l have associatedthe lifting mechanism in mutually eoaeting pairs. By this construction,I have been enabled to substantially double the lift without adding tothe minimum height of the platform from the floor. This is extremelyimportant heverse hearing ride in slots al TRUCK.

7 T, risen rear '4 Eerie H0. $33,913.

cause it is essential that these trucks be low and desirable that theyhave a large litt. L consider this feature both useful, and; broadlynew. i M

In the drawings :.-Figure 1 is a side elevation of my truclr" partly incross-section; Fig. 2 is a side elevation partly in cros section, of: mytruck; Fig. 3 is a plan View thereofgend is a section on line of'Fig. 1.A The truck comprises an eievatingplatform A usually made andconstructed or" channel metal in skeleton term, as shown in 3. The truckframe proper coingorises the hers B and B, each of broad form. Bolted tothe inturned portions and at the rear end of the B and B is an axle Chaving turned-clown. o'rtions at l s outer ends to accommodatethe wheelsat and of the truck. Sec to the front end of the bars B and B" are uWardly projecting supporting brackets D l1l1' D' carrying a support 1tor the swivel (Z steering front wheel (5 The swivel (5" hes e transd'upon its upper surface which earl e spin (E which engz the bQAIiHf S (iupon the lJ-shepeu incl ioer a through a bearing e top which, as at 05vflfil a handle (Z carryi a 'oss-ror ox Upon these gudgeons mounted 2ill in gs and 2 has lot e and recess e therein as s low;- the can: 6

'l is in all respects mg each of these cam and f, slotted to embrace 'asshown in Figs. 1

carrying cam rollers} ends and prolonged, ir.

ends

Fig. 4). g and 9 form another revolubly mounted upon the same shaft butin op posite phase. 9 and g and "g and 9 complete the cam equipment ofthe shaft 9 upon the op- Links l and Z connect shaft 9 with the shaft mat the rear of the truck, while secured to the shaft 4% are a set ofcams cor- "responding in every detail with the cams just described, andupon the frame-bars B and B and the platform A are bearing blocks havingsmooth and rack portions for coiiperation with these cams in preciselythe manner just described. Secured to the links Z at two points thereofare forks a, n, and 0 and 0'. Rising from the frame bars 13 and B arebrackets p and p and dependent from the bottom of the platform A arebrackets 79 and 72 these brackets being provided with pins, such as g, 9q, and 9 These pins are at all times embraced between the forks n and n,0 and 0 and serve to hold platform A in prescribed relation to a base B.Those at the rear function precisely as do those at the front. Upon theswivel platform of theportion D hereinbefore al-' luded to is mounted apair of brackets and s carrying rollers s and's bearing against a plate8 mounted on the front of the plat form A, as clearly shown in Fig. 2.

The operation of my truck is as follows: Referring to Fig. 1, when it ISdesired to raise the platform A, the handle d is moved until itscross-rod d takes into the slots 6 of the cams e and (2 These cams arethen turned do'vvn about their gudgeons e and e,

' their bearing. surfaces e drawing forks f and f forward in an obviousmanner. When the; cams reach a substantially horizontal position, therollers f and f onthe forks 7 drop into the recess 6 just as these meansof the handle (i recesses go past center relatively to the shaft 7 andthe gudgeons e and e; As the cam is dropped through this position oracross centers, it is obvious that there is a toggle action and that thelinks 7 and f can not be retracted, and the platform, therefore, islocked in elevated position. When the platform is to be lowered, thecams are again swung back past center by and cross-rod d". As the links7 and are drawn forward as above described, the shaft 9 is drawnforward, and, through the intermediary of the links I and Z, the shaft mis also drawn the shaft 9 tively, force the platform A and the baseportion B apart in an obvious manner. Thus it may be seen that the camsk and h, 9 9 ,9 and g of Fig. 1 operate to bodily raise the shaft 9carrying platform A, Whi'le the cams 9, 9' 9 and 9 carried up with tendto still further bodily raise platform A, while a simultaneous andexactly similar set of operations is going on at the rear of the truck.The forks n, n and 0 and 0' keep the platform from being separatedfarther than the limit prescribed by the lifting devices, while therollers s and 8 keep the platform A from riding forward with the shaftsg and m. It is to be 5 particularly noted that while I have provided,substantially, a double-lift mechanism, yet, by placing my cams inpairs, I have not increased the minimum distance of the top platformfrom the floor. This is a very important feature of my invention, sincethese trucks for successful and practical operation should be as low aspossible, but yet it isvery have a comparatively large lift.

Having now described my invention but recognizing that many departuresand modifications may be made from the specific form in which I havechosen here to illustrate it, the scope of the invention being moretruly defined and bounded in the following claims, I claim I. In anelevating truck, a base member, a vertically movable lifting platform, aframe intermediate said platform and said member adapted to belongitudinally movable with respect to said member, cam devices on saidframe in engagement with said base member and platform, and adapted toroll. thereon when said frame is actuated, cams on said base, connectingmeans between said cams and said frame, a steering handle on saidbaseand means independently movable therein to engage said desirable thatthey.

other cams 1 s, LEA. s a jut, cilgagiiig .7 v u i I M ,ains tne case,engaging a he cams on platform, said i. paged rolling contact with saidr'iei'ices, means to shift the frame longituflinally ivl'iereby theplatform and the base may s unrated, including means whereby may belOClTGCi in its raiscil truck. including a base, *ially-n'icvahle e :aitbase and "plan therei handle, and means asst "E13 handle 'hcreby shelifting Lori-cl to-eii'ect their lilting iudiirig means whereby thecares ii in their displaced i in an hit i in said slots and recesses,the Whole being so arranged that the cams and links form toggles.

7. in a mechanism of the class described including a base, ancl amovable platform,

a frame intermediate the base and the g iiattcrin, l1. devices on theframe having rel e ,gement with said base and platform ana means wherebythe rate of vertical nwvenient of the platform varies with thelongitudinal displacement or" the trains.

8. In an apparatus of the class described, including a base and aplatform movable away from the base, means for moving the platform awayfrom the base, said means incliii'ling a frame, cam devices mounted onthe frame and engaged in rolling contact, respectively, with the baseand the platform, said cam devices being so arrange that the liftingrate (if the platferni varies with the tlisplacenient of the cams fromtheir starting position, and devices sperable at the will of theOperator t0 move said frame.

GEORGE L. MASON. Witnesses:

W0 A. B00111, Qasenmn VJ LLIs.

an i 313

